Hay baled from an individual farm can vary significantly in quality due to the growing factors affecting the crop being baled. The factors of soil type, exposure to the sun and wind, plant population and ground moisture are some of the major conditions that determine the amount of hay, the moisture of the hay and the components of the hay in different parts of the farm. Moisture, windrow thickness and consistency of the crop effect the weight of the bale as it is packed into a round or square hay bale. Bale weights can vary as much as 30% in the same field with the same baler. Moisture can vary as much as 50% from bale to bale in the same field of hay. These variations affect the value of the hay from bale to bale.
The feeding quality of a bale is directly related to the selling price of the hay or to the amount of hay a producer's livestock will consume. It has been the practice to core the bale after producing it, do a laboratory analysis of the bale and then associate those results with the bale before selling it or feeding it.
Most hay is sold on a weight basis. The practice of weighing hay once on a truck either at the shipping or receiving end is an accepted means of determining weight. But in many cases, this method requires extra distances for traveling to scales to attain this information and may result in adjustments being made to the bales on the truck to increase or decrease the loaded amount.
Hay baled outside of an accepted range will have several problems: if it has been baled too wet, it will heat once stacked with other bales and can spoil or cause the entire stack to get hot and even burn; hay baled too dry, will have low feed quality and acceptance. Previous methods for monitoring moisture have been limited to the operators of balers noting moisture problems and stopping the baler to mark the bales with problems.
Chemical hay preservatives are commonly used to preserve hay that is baled above the moisture level of 16%. Monitoring the amount of preservative applied to each bale is done on a general basis and there is no way to determine if individual bales have been treated with the correct amount of preservative after they have been baled.
Different hay fields and different parts of the same field will have different levels of hay quality. Sorting bales by their point of origin can be an indication of the type and quality of the hay in a particular bale. The state of the art is believed to include the following US patents:
4,688,026August 1987Scribner et al.6,378,276April 2002Dorge et al.6,248,963June, 2001Gottlober6,817,522November 2004Brignone, et al.6,712,276March 2004Alabi et al.6,693,539February 2004Bowers, et al.6,377,058 B1June, 2002Pemrick